implement support for Jakarta Data events

(no events for reactive repos)

tooling/metamodel-generator/src/main/java/org/hibernate/processor/ClassWriter.java

@@ -108,6 +108,12 @@ private static StringBuffer generateBody(Metamodel entity, Context context) {
 
 			pw.println();
 
+			// TODO: move this!
+			if ( context.addDependentAnnotation() && context.isDataEventPackageAvailable()
+					&& entity.isImplementation() && !entity.isReactive() ) {
+				pw.println("\t@Inject private Event<? super LifecycleEvent<?>> event;\n");
+			}
+
 			final List<MetaAttribute> members = entity.getMembers();
 			for ( MetaAttribute metaMember : members ) {
 				if ( metaMember instanceof InnerClassMetaAttribute innerClass ) {

tooling/metamodel-generator/src/main/java/org/hibernate/processor/Context.java

@@ -92,6 +92,7 @@ public final class Context {
 	private AccessType persistenceUnitDefaultAccessType;
 	private boolean generateJakartaDataStaticMetamodel;
 	private boolean quarkusInjection;
+	private boolean dataEventPackageAvailable;
 
 	// keep track of all classes for which model have been generated
 	private final Set<Metamodel> generatedModelClasses = new HashSet<>();
@@ -224,6 +225,14 @@ public void setQuarkusInjection(boolean quarkusInjection) {
 		this.quarkusInjection = quarkusInjection;
 	}
 
+	public boolean isDataEventPackageAvailable() {
+		return dataEventPackageAvailable;
+	}
+
+	public void setDataEventPackageAvailable(boolean dataEventPackageAvailable) {
+		this.dataEventPackageAvailable = dataEventPackageAvailable;
+	}
+
 	public Elements getElementUtils() {
 		return processingEnvironment.getElementUtils();
 	}

tooling/metamodel-generator/src/main/java/org/hibernate/processor/HibernateProcessor.java

@@ -243,6 +243,9 @@ private boolean handleSettings(ProcessingEnvironment environment) {
 		final PackageElement quarkusOrmPackage =
 				context.getProcessingEnvironment().getElementUtils()
 						.getPackageElement( "io.quarkus.hibernate.orm" );
+		final PackageElement dataEventPackage =
+				context.getProcessingEnvironment().getElementUtils()
+						.getPackageElement( "jakarta.data.event" );
 
 		PackageElement quarkusOrmPanachePackage =
 				context.getProcessingEnvironment().getElementUtils()
@@ -265,6 +268,7 @@ && packagePresent(quarkusOrmPanachePackage) ) {
 		context.setAddGeneratedAnnotation( packagePresent(jakartaAnnotationPackage) );
 		context.setAddDependentAnnotation( packagePresent(jakartaContextPackage) );
 		context.setAddTransactionScopedAnnotation( packagePresent(jakartaTransactionsPackage) );
+		context.setDataEventPackageAvailable( packagePresent(dataEventPackage) );
 		context.setQuarkusInjection( packagePresent(quarkusOrmPackage) );
 		context.setUsesQuarkusOrm( packagePresent(quarkusOrmPanachePackage) );
 		context.setUsesQuarkusReactive( packagePresent(quarkusReactivePanachePackage) );

tooling/metamodel-generator/src/main/java/org/hibernate/processor/annotation/AnnotationMetaEntity.java

@@ -685,6 +685,11 @@ boolean needsDefaultConstructor() {
 		return null;
 	}
 
+	@Override
+	public boolean isReactive() {
+		return usingReactiveSession(sessionType);
+	}
+
 	private boolean isPanacheType(TypeElement type) {
 		return context.usesQuarkusOrm() && isOrmPanacheType( type )
 			|| context.usesQuarkusReactive() && isReactivePanacheType( type );

tooling/metamodel-generator/src/main/java/org/hibernate/processor/annotation/LifecycleMethod.java

@@ -7,6 +7,9 @@
 
 import javax.lang.model.element.ExecutableElement;
 
+import java.util.Set;
+
+import static java.lang.Character.toUpperCase;
 import static org.hibernate.processor.util.Constants.LIST;
 import static org.hibernate.processor.util.Constants.UNI;
 
@@ -60,21 +63,24 @@ public boolean hasStringAttribute() {
 		return false;
 	}
 
+	private String capitalize(String string) {
+		return toUpperCase(string.charAt(0)) + string.substring(1);
+	}
+
+	static final Set<String> eventTypes = Set.of("insert", "update", "delete");
+
 	@Override
 	public String getAttributeDeclarationString() {
 		StringBuilder declaration = new StringBuilder();
 		preamble(declaration);
 		nullCheck(declaration, parameterName);
+		preEvent(declaration);
 		if ( !isReactive() ) {
 			declaration.append( "\ttry {\n" );
 		}
 		delegateCall(declaration);
-		returnArgument(declaration);
+		returnArgumentReactively(declaration);
 		if ( !isReactive() ) {
-			if ( returnArgument ) {
-				declaration
-						.append( ";\n" );
-			}
 			declaration.append( "\t}\n" );
 		}
 		convertExceptions( declaration );
@@ -82,10 +88,77 @@ public String getAttributeDeclarationString() {
 			declaration
 					.append( ";\n" );
 		}
+		postEvent(declaration);
+		returnArgument(declaration);
 		declaration.append("}");
 		return declaration.toString();
 	}
 
+	private void postEvent(StringBuilder declaration) {
+		if ( annotationMetaEntity.getContext().isDataEventPackageAvailable()
+				&& annotationMetaEntity.getContext().addDependentAnnotation()
+				&& eventTypes.contains( operationName )
+				&& !isReactive() ) {
+			final String postEventType = "Post" + capitalize( operationName ) + "Event";
+			annotationMetaEntity.importType( "jakarta.data.event." + postEventType );
+			declaration
+					.append( "\tevent.select(new TypeLiteral<" )
+					.append( postEventType )
+					.append( "<" )
+					.append( annotationMetaEntity.importType( entity ) )
+					.append( ">>(){})\n\t\t\t.fire(new " )
+					.append( postEventType )
+					.append( "<>(" )
+					.append( parameterName )
+					.append( "));\n" );
+		}
+	}
+
+	private void preEvent(StringBuilder declaration) {
+		if ( annotationMetaEntity.getContext().isDataEventPackageAvailable()
+				&& annotationMetaEntity.getContext().addDependentAnnotation()
+				&& eventTypes.contains( operationName )
+				&& !isReactive()) {
+			final String preEventType = "Pre" + capitalize( operationName ) + "Event";
+			annotationMetaEntity.importType( "jakarta.data.event." + preEventType );
+			annotationMetaEntity.importType( "jakarta.data.event.LifecycleEvent" );
+			annotationMetaEntity.importType( "jakarta.enterprise.util.TypeLiteral" );
+			annotationMetaEntity.importType( "jakarta.enterprise.event.Event" );
+			annotationMetaEntity.importType( "jakarta.inject.Inject" );
+			declaration
+					.append( "\tevent.select(new TypeLiteral<" )
+					.append( preEventType )
+					.append( "<" )
+					.append( annotationMetaEntity.importType( entity ) )
+					.append( ">>(){})\n\t\t\t.fire(new " )
+					.append( preEventType )
+					.append( "<>(" )
+					.append( parameterName )
+					.append( "));\n" );
+		}
+	}
+
+	private void returnArgument(StringBuilder declaration) {
+		if ( returnArgument && !isReactive() ) {
+			declaration
+					.append( "\treturn " )
+					.append( parameterName )
+					.append( ";\n" );
+		}
+	}
+
+	private void returnArgumentReactively(StringBuilder declaration) {
+		if ( isReactive() ) {
+			if ( returnArgument ) {
+				declaration
+						.append( "\n\t\t\t.replaceWith(")
+						.append(parameterName)
+						.append(")");
+			}
+		}
+	}
+
+
 	private void convertExceptions(StringBuilder declaration) {
 		if ( operationName.equals("insert") ) {
 			handle( declaration,
@@ -102,23 +175,6 @@ private void convertExceptions(StringBuilder declaration) {
 				"jakarta.data.exceptions.DataException");
 	}
 
-	private void returnArgument(StringBuilder declaration) {
-		if ( returnArgument ) {
-			if ( isReactive() ) {
-				declaration
-						.append( "\n\t\t\t" )
-						.append(".replaceWith(")
-						.append(parameterName)
-						.append(")");
-			}
-			else {
-				declaration
-						.append("\t\treturn ")
-						.append(parameterName);
-			}
-		}
-	}
-
 	private void delegateCall(StringBuilder declaration) {
 		if ( isReactive() ) {
 			// TODO: handle the case of an iterable parameter
@@ -179,7 +235,7 @@ private void argument(StringBuilder declaration) {
 				if ( isReactive() ) {
 					declaration
 							.append("All")
-							.append("(")
+							.append("((Object[]) ")
 							.append(parameterName)
 							.append(")");
 				}

tooling/metamodel-generator/src/main/java/org/hibernate/processor/model/Metamodel.java

@@ -60,4 +60,8 @@ public interface Metamodel extends ImportContext {
 	List<AnnotationMirror> inheritedAnnotations();
 
 	String javadoc();
+
+	default boolean isReactive() {
+		return false;
+	}
 }